PLMERIDIANS(3plplot)

💫 PLMERIDIANS (3plplot) — the PLplot API one 💫

okay bestie so this is plmeridians from the PLplot API, and it's literally the glow-up your map plots have been waiting for 🌍✨

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✨ NAME ✨

plmeridians — draws latitude and longitude lines, aka the grid that makes your globe look like a globe and not a sad blob 🎀

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🌸 SYNOPSIS 🌸

plmeridians(mapform, dlong, dlat, minlong, maxlong, minlat, maxlat)

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🦋 DESCRIPTION 🦋

So basically: this displays latitude and longitude on the current plot. That's it, that's the vibe. And because it's classy, the lines get plotted in the current color</> and current line style</> — whatever you set up before calling this, it respects it, no cap 💅

Redacted form (yes, it's the same thing, it's giving "same energy, shorter outfit"):

plmeridians(mapform, dlong, dlat, minlong, maxlong, minlat, maxlat)

Also, this function is used in example 19 — go look, iykyk 👀

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🎀 ARGUMENTS 🎀

• mapform (PLMAPFORM_callback(3plplot), input) — a user-supplied function that transforms coordinate longitudes and latitudes into a plot coordinate system. by using this transform we can change from a longitude, latitude coordinate to a polar stereographic project, for example 🧭🌐. initially, x[0]..[n-1] are the longitudes and y[0]..y[n-1] are the corresponding latitudes. after the call to mapform(), x[] and y[] should be replaced by the corresponding plot coordinates. if no transform is desired, mapform can be replaced by NULL — lowkey iconic, just pass NULL and move on 🌈
• dlong (PLFLT(3plplot), input) — the interval in degrees at which the longitude lines are to be plotted. your spacing, your rules 📏
• dlat (PLFLT(3plplot), input) — the interval in degrees at which the latitude lines are to be plotted. same deal, but for the horizontal-ish besties 📐
• minlong (PLFLT(3plplot), input) — the value of the longitude on the left side of the plot. careful though, bestie: the value of minlong must be less than the value of maxlong, and the quantity maxlong-minlong must be less than or equal to 360 🚨 that's not a suggestion, that's the rules
• maxlong (PLFLT(3plplot), input) — the value of the longitude on the right side of the plot 🫶
• minlat (PLFLT(3plplot), input) — the minimum latitude to be plotted on the background. you can always use -90.0 because anything outside the plot window gets automatically eliminated anyway (the plot said "not in my house" 💀). however, the program will be faster if you can reduce the size of the background plotted — so being specific is literally self-care ⚡
• maxlat (PLFLT(3plplot), input) — the maximum latitudes to be plotted on the background. and again, you can always use 90.0 since the boundary outside the plot window is automatically eliminated ✂️✨

quick reminder that minlong/maxlong have that hard constraint while minlat/maxlat are chill — don't mix them up 🙈

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👑 AUTHORS 👑

Many developers (who are credited at http://plplot.sourceforge.net/credits.php) have contributed to PLplot over its long history. fr fr, a whole squad, a whole legacy 🫡💜

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🌟 SEE ALSO 🌟

PLplot documentation at http://plplot.sourceforge.net/documentation.php — go read it, it's giving lore 📚

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k that's the whole page, mwah 💋 this was PLMERIDIANS(3plplot) from the PLplot API, dropped August, 2026 — screenshot it, cite it, plot your meridians responsibly 🍓🧚‍♀️